DE3543414A1 - FLAME RETARDANT COMBINATION - Google Patents

Description

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35434H

FLAME RETARDANT COMBINATION

The invention relates to flame retardant mixtures in the form microcapsules are incorporated into polymeric organic material.

It has been found that microcapsules, which are a mixture of

a) halogenated, flame-retardant organic compounds (Component a) and

b) an inorganic oxide, hydroxide, borate or phosphate (component b),

included, excellent as a flame retardant for polymeric organic Fabrics are suitable.

Halogenated, flame-retardant organic compounds are to be understood as meaning, above all, the chlorine and / or bromine-containing compounds known as such, the molecular weight of which is 20 to 75%, preferably 40 to 75 %, due to the halogen atom content; the number of carbon atoms to halogen atoms is about 5: 1 to 1: 1 here. The compounds are preferably used melt determined ie at ambient temperature between 50 and 35O ^e C are.

Particularly preferred are, for example, tetrabromophthalic anhydride or -imide; halogenated carboxylic acid esters, e.g. 2,2-bis- (bromomethyl) -3- bromopropyl carbonate; Tribromophenyl carbonate; Shark terephthalic acid ester, e.g., bis (2,3-dibromopropyl) terephthalate; halogenated diphenyl oxide, e.g., decabromodiphenyl ether; halogenated benzene, toluene, xylene or ethylbenzene, e.g. hexabromobenzene, pentabromotoluene, tetrabromoxylene and pentabromoethyl benzene; halogenated cyclic (saturated or unsaturated) compounds, e.g. hexabromocyclodecane, dibromo-

ORiGlNAL INSPECTED

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methyl-dibromocyciohexane, hexabromomethylbenzene, perchlorpentacyclodecane; halogenated bisphenols, which may have been dialkoxylated, e.g., halogenated alkyl aryl ethers, especially 2,2-bis- [4- (2, '3'-dibromopropoxy) -3,5-dibromophenyl] propane; Bicyclo [2,2,1] -heptane-2,3-dicarboxylic acid derivatives, e.g. the compound of the formula

Br 6

brominated polymers such as poly (tribromostyrene) and brominated polyphenyl ethers as well as chlorinated paraffin with a chlorine content between 20 and 75 percent by weight. Among these compounds are the chlorinated ones Paraffins and the brominated cycloaliphatic compounds, e.g. Hexabromocyclododecane and the brominated diphenyls and diphenyl ethers, especially those of the formula

where η = 0 or 1 and χ and y x + y 4 to 10 are preferred.

2 to 5, where the sum

Component b is preferably an oxide, hydroxide, borate and / or a Phosphate of Al, Mg, Al, Si, Sn, Sb, Bi, Ti, Fe, Zn, Mo or tungsten, especially magnesium or aluminum hydroxide, antimony or bismuth oxide or zinc borate, especially Sb2U3, Sb2U5 or zinc borate, especially

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The weight ratio of components a: b is generally between 5: 1 and 1: 2, preferably between 4: 1 and 1: 1, in particular between 3: 1 and 3: 2.

In general, the diameter of the microcapsules is up to 100 .mu.m, preferably up to 75 .mu.m, in particular up to 50 .mu.m. The weight ratio of wrapping material to capsule contents (tare to net) is generally 1: 1 to 1: 150, preferably 1: 5 to 1: 100, in particular 1:25 to 1:75 ("Fill" approx. 50 to 99.3%, preferably 80 to 99 %, in particular 96 to 98.6%).

Among the materials that can be made flame-retardant according to the invention are In general, all organic polymers should be mentioned, in particular polyolefins (e.g. polyethylene, polypropylene and their copolymers), linear saturated polyesters (e.g. polyethylene terephthalate, polybutylene terephthalate etc.), unsaturated polyesters (e.g. based on maleic acid), polyamides (e.g. all types of nylon), polyacrylates and methacrylates (e.g. PMMA), polystyrene, ABS polymers, polyurethane, polyacrylonitrile and its copolymers, cellulose esters, epoxy resins and polyvinyl chloride.

The microcapsules are incorporated into the polymer masses by generally known methods incorporated. For example, you can add the monomers or prepolymers before the polymerization or the finished polymers in the extruder be inflicted.

The microcapsules can also be processed into a masterbatch (concentrate) and added as such to the polymers. Corresponding concentrates generally contain 20 to 90, preferably 40 to 80 Weight percent microcapsule material, the remainder is an im intended Substrate easily spreadable (compatible) polymer. The concentrate can also contain a suspension of the microcapsules (preferably 20 to 90, in particular 40 to 80 percent by weight capsules) in one be organic solvents.

ORIGINAL INSPECTED

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The capsule material (the envelope) is preferably one in the substrate (the polymer mass to be made flame-resistant) insoluble polymer, see above that it is ensured that the flame-retardant compound mixture in the originally used form (microcapsules) is retained until the substrate is heated to a temperature close to the flash point of the substrate lies (approx. 200 * C).

The capsule material (the enveloping membrane) consists e.g. of rubber arabic, Gelatin, cellulose acetate phthalate or phenol formaldehyde resin .

The flame retardant compounds, components a and b, are generalized according to known methods processed into microcapsules.

The microencapsulation brings against the use of flame retardants Without further measures, some essential advantages: There is no corrosion of the substrate processing machines by the flame retardant compounds in place; the light stability of the treated Substrate is not affected by the flame retardants; below the processing temperature the substrates volatile flame retardants do not vaporize / sublime; easily migrating flame retardant compounds cannot "bloom" on the substrate surface. Quite essential is also the fact that flame retardants in microcapsules have a noticeably better effect than homogeneously distributed flame retardants.

It can be assumed that the encapsulated flame retardants act as follows: When a temperature close to the flash point (approx. 200 ^° C.) is reached, the capsules break open, the inorganic compounds react with the halogenated organic compounds, the reaction products penetrate the substrate and develop the flame retardant effect .

ORIGINAL INSPECTED

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The invention also relates to a method for microencapsulation one or more substances, which is characterized in that this, in the presence of urea to a cellulose acetate phthalate solution and then add a (known) coacervating agent to the solution Funds inflicts.

In general, the microcapsules can be prepared by known methods or be prepared in analogy to Examples 1 to 3.

In the following examples, parts mean parts by weight and Percentages by weight. The temperatures are given in degrees Celsius.

example 1

Production of microcapsules with a gelatine / gum arabic membrane:

A 10% aqueous gelatin solution and a 10% aqueous gum arabic solution are prepared, 50 parts of each of the two solutions are mixed, 400 parts of water at 45 ° are added while stirring, 66.7 parts of chlorinated paraffin (70 % Chlorine content, CP 70 from Hoechst) and 33.3 parts of Sb2Ü3 add to the solution and stir until a homogeneous suspension is obtained. Then 10 η acetic acid is added until pH 4 is reached. Gelatin / arabic gum membranes are formed, which envelop particles of paraffin and Sb2Ü3. It is first cooled slowly to 25 ', then very quickly to 10 ", the membranes solidifying. To harden the membranes, 40 parts of a 25 percent aqueous glutaraldehyde solution are added, the mixture is stirred for a further 8 hours, after which the capsules are filtered off, washed and dried.

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Example 2

Manufacture of microcapsules with a gelatin membrane:

100 parts of a 10% aqueous gelatin solution are placed under tubes, heated to 45 ", with 250 parts (45 ° warm) water and 20 parts Sodium hexametaphosphate (5%) / water mixture added. Always under 66.7 parts of chlorinated paraffin (as indicated in Example 1) and 33.3 parts of SD2O3 are then added with stirring; when the mixture is homogeneous is, the pH is adjusted to 4 with 10 η acetic acid, whereby the gelatine forms a membrane around the chlorinated paraffin and Sb203 ~ particles and forms microcapsules. The further treatment of the capsules takes place as indicated in Example 1.

The sodium hexane metaphosphate is produced by Gross Giuglio SPA, Monza, Italy, delivered.

Example 3

Production of microcapsules with a cellulose-acetate-phthalate membrane:

40 parts of a five percent aqueous cellulose acetate phthalate Solution are mixed with 150 parts of water, 2 parts of urea, 66.7 parts of chlorinated paraffin (as in Example 1) and 33.3 parts of SD2O3, stirred until a homogeneous suspension is formed, then Glauber's salt is added to coacervate the cellulose acetate phthalate and finally citric acid is added until pH 4 is reached. The mixture is stirred until the capsule shells have completely polymerized and filtered the capsules, washes and dries them. Instead of the chlorinated paraffin, the same amount of octa- or decabromodiphenyl can also be used oxide or 1,2-bis (pentabromophenyloxy) ethylene can be used.

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Example 4

10 parts of microcapsules according to Example 3 are mixed with 90 parts of commercially available high-pressure polyethylene ("Lupolen 2420 F" from BASF), which has a "Melt Flow Index" (MFI) of 0.6 to 0.9 (measured at 190 "and 2 , 16 kp), machined and mixed in a rolling mill at 150 ". Plates 3 mm thick are produced from the mass obtained under a pressure of 1.25 kg / cm ² and then 18.75 kg / cm ^{2 for 90 seconds each time.} The flammability is then tested using the UL 94 test (Underwriters Laboratories Inc.); it corresponds to classification V-2.

Example 5

20 parts of microcapsules according to Example 3 (1st part) are in a rolling mill for 3 minutes at a. 160 ° mixed with 80 parts of commercially available ABS (Cycolac T 10,000) and pressed for 90 seconds under a pressure of first 1.25 kg / cm ² , then 18.75 kg / cm ² to form 3 mm thick sheets. According to the UL 94 flammability test, the classification of the panels is VO.

Example 6

Containing 20 parts of octabromodiphenyl oxide and Sb2U3 in a ratio of 5: 3 Microcapsules are processed analogously to the procedure of Example 5 with ABS. In the U.L. 94 test is the classification of the obtained Plates V-O.

N.B. According to the U.L. 04 test there are three classifications: the best is V-O, the other two are V-I and V-2. If a substrate doesn't have any If it receives a designation, it says that it did not pass the test conditions because it was too flammable.

Claims (4)

35434H SANDOZ-PATENT-GMBH Case 153-4968 7850 Lörrach FLAME PROTECTION AGENT COMBINATION Patent claims 1. Flame retardant combination, consisting of microcapsules that contain a Mixture of a) halogenated, flame-retardant organic compounds and b) contain an inorganic oxide, hydroxide, borate or phosphate. 2. microcapsules according to claim 1, which is a mixture of chlorinated Contain paraffin, octa- or decabromodiphenyl oxide and antimony trioxide. 3. Process for the flame retardancy of polymeric organic materials, characterized in that microcapsules according to claim 1 or 2 are introduced into these materials. 4. Flame-retardant polymeric organic substances, characterized in that that they contain microcapsules according to claim 1 or 2 as a flame-retardant agent. 3700 / HW / HB